Dental obtunder.



Nol 792,836. PATENTED JUNE 20, 1905. B. A. LOVELESS.

DENTAL OBTUNDER.

APPLICATION FILED OCT. 25,1904.

i K NWIIIIIIIIIIIIIIIIIIJIIIIIIIII IIIIIIII/ 02 \\\\\\\\\\|w1, I l l l WITNESSES [1V EH10)?" H M QM Patented June 20, 1905.

PATENT OFFICE.

BURT A. LOVELESS, OF FULTON, NEW YORK.

DENTAL OBTUNDER.

SPECIFICATION forming part of Letters Patent No. 792,836, dated June 20, 1905,

Application filed October 26, 1904. Serial No. 229,926.

To all whom it may concern.-

-Be it known that I, BURT A. LovELEss, of Fulton, in the county of Oswego, in the State of New York, have invented new and useful Improvements in Dental Obtunders, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

This invention relates to improvements in dental obtunders by which a liquid anesthetic is injected under high pressure into and through a tooth or other osseous part to be treated to desensitize the same. In this class of instruments it is not only necessary to eject the anesthetizing agent through a minute needle-passage under a high degree of pressure, but it is also necessary to maintain a constant and uniform pressure during the discharge.

My object, therefore, is to provide a simple and practical means whereby the anesthetizing agent may be easily and quickly injected into and through a tooth or osseous part under a constant high degree of pressure, the specific object being to obtain the required pressure with the least exertion.

In the drawings, Figure 1 is a side view of an instrument embodying the features of my invention for the purpose described. Fig. 2 is a longitudinal sectional view of the same, taken on line 2 2, Fig. 1.

In carrying out the objects stated I provide a cylinder 1 with a chamber 2 for receiving the anesthetizing agent and in which is movable a close-fitting metal piston 3. One end of the cylinder is equipped with a hollow needle-point i, havinga needle-passage 5, through which the anesthetic is ejected. The other end through which the piston-rod passes is provided with a suitable screw-cap, which forms a stufling-box 6 to prevent leakage of the desensitizing agent around the piston. The outer end of the piston-rod is provided with a threaded portion 7 and a suitable hand piece or knob 8, by which the piston may be rotated, the threaded portion 7 being fitted in athreaded opening 9 in one end or hub 10 of a yoke 11. The other end of this yoke has a similar hub 12, which is fitted upon and secured to the adjacent end of the cylinder 1, and these hubs 10 and 12 are rigidly connected by diametrically opposite arms 13, thus forming a suitable han dle by which the instrument maybe held when 1n use.

The threaded aperturein which the screw of the piston-rod plays is preferably formed in a separate bushing 14, which is'firmly secured in the hub 10, but may be removed and replaced by a new bushing when worn.

In operation the operator grips the arms 13 in one hand and with the other hand on the screw-knob 8 applies the needle-point to the afflicted member and then gently rotates the screw to move the piston toward said point, thereby injecting the anesthetic into the part being treated.

It is evident that by the use of the screw a maximum degree of pressure may be easily obtained and maintained with a minimum degree of exertion and that the screw automatically locks itself in its adjusted position, thereby rendering the operation of administering the anesthetic more steady and reliable and less liable to accidental displacement of the needle during the operation.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

1. A dental obtunder comprising a cylinder containing an anesthetizing agent and having ahollow needle-point on one end, a piston movable in the cylinder and having its rod projecting through the end opposite the needlepoint, the outer end of the piston-rod being screw-threaded and provided with a handpiece, and a yoke secured to the cylinder and having a threaded hub receiving the screw-threaded portion of the rod.

2. A dental obtunder consisting of a cylinder having one end provided with a hollow needle-point, a threaded hub secured to the opposite end of the cylinder in axial alinement therewith, and a screw engaged with thethreaded hub and having one end entering the cylinder and its other end provided with a handpiece whereby the screw is rotated.

In witness whereof I have hereunto set my hand this 21st day of October, 1904.

BURT A. LOVELESS.

Witnesses:

OLAUpE E. GUILE, H. B. OoLLINs. 

